Francis W. Parker, Francis W. Parker School Year Book .The course in science, vol. V, Chicago, Faculty of the Francis W. Parker School, 1918, p. 53.

The caddis-larva has a little house around him. Sometimes his house is made of plant-stems and hollow seeds, and sometimes little stones. When his house is made of plant stems or hollow reeds, he lives in swift-flowing stream. When he lives in swift-flowing streams, he cannot swim much, but the things he eats come with the stream.

The inside of his house is very soft. He has two or three hooks at the end of his body, and he hooks himself in. The caddis-larva eats smaller animals than he, and he is so juicy that fish like to eat him, and that is the reason he makes a house around himself.